The winter holidays are now behind us, but it seems I missed one of the biggest pranks of 2010 – the green river of Goldstream Park.

It happened on December 29, 2010, in Victoria’s peaceful Goldstream Park. The waters of the river suddenly became neon green, and everyone passing by it rubbed their eyes to make sure what they were seeing wasn’t just an illusion. It was very real, but was it that made Goldstream River look so alien-like? After an hour or so, the fluorescent coloring vanished, but the questions about the bizarre phenomenon remained unanswered.

After analyzing the neon-green water, the local Environment Ministry said it was the result of a chemical called “fluorescein”. Neither the substance itself nor its products of degradation are toxic, and experts believe that fish and their habitat were not affected, judging by the concentration and flow rate of the river.

Authorities haven’t yet identified the culprits, but believed the dumping of fluorescein in the Goldstream River was just a holiday season prank.